Tone color changing device for electronic musical instruments

ABSTRACT

A simple, versatile, and quickly operable tone color changing device comprising a combination of a variable means which may be a multiposition changeover switch or a plurality of variable resistors interlinked with an operable means such as a kneelever, and a selecting means preferably consisting of a multiposition, double-circuit changeover switch connected with two different tone color signal sources.

United States Patent Inventor Akin Nakada llamamatsu-shl, Japan Appl. No. 812,816 Filed Apr. 2, 1969 Patented Sept. 7, 1971 Assignee Nippon Gakkl Seizo Kabushlki Keisha llamlmatsu-shl, Shiznoka, J pan TONE COLOR CHANGING DEVICE FOR ELECTRONIC MUSICAL INSTRUMENTS 7 Chlmg tbnwingl igs.

U.S.C1 84/l.19, 84/1.2l, 84/1.22 Int. CL G101: 1/06, G10h 5/00 fieldofsearch 84/1.0l,

[56] Reierences Cited UNITED STATES PATENTS 2,493,358 1/1950 Oswald 84/1 .19 2,557,133 6/1951 Mork 84/1.19X 2,585,357 2/1952 Wayne 84/1 1 7 3,217,081 11/1965 Nakada 84/1.27

Primary Examiner-Milton O. Hirshfield Assistant Examiner-Stanley J. Witkowski Attorney-Holman & Stern TONE COLOR CHANGING DEVICE FOR ELECTRONIC MUSICAL INSTRUMENTS BACKGROUND OF THE INVENTION This invention relates to a tone color changing device to be used in an electronic musical instrument, and more particularly to a type thereof in which the change over of the tone color from one kind to another or mixing of two tone colors is attained by a simple, .versatile, and quickly-operable procedure.

Heretofore, in the conventional electronic musical instruments, the tone color has been selected and determined by the combination of a number of tone levers or stop tablets. In some of the known types of musical instruments, such an operation was carried out by. a preset device which could provide a combination of tone colors preset beforehand. However, in all of such devices, it was impossible to impart a different tone color merely to a selected tone which was to be emphasized during the playing of the musical instrument with both hands.

SUMMARY OF INVENTION Therefore, the primary object of the present invention is to eliminate the above mentioned drawback of the conventional tone color changing devices, and to provide a novel tone color changing device, which is capable of changing tone colors promptly, so that it may be adapted to the present day music in which the tempo thereof is very fast, and thereby affords a more detailed expression in the music.

Another object of the present invention is to provide a novel tone color changing device by which the tone color can be changed selectively with respect to a particular musical tone to be emphasized without requiring hand manipulation.

Still another object of the invention is to provide a tone color changing device in which means for producing at least two tone color signals are provided, and these are changeable over at will from one to the other or vice versa, or a mixture of these tone color signals at either a predetermined or a variable ratio can be obtained selectively from the output terminals of the device.

These and other objects of the present invention are satisfactorily accomplished by a novel construction of the tone color changing device which comprises means for producing at least two tone color signals, an operable means allowing promptly operation without requiring hand manipulation, a variable means interlinked with said operable means such as a knee lever, and a tone color selecting means which, depending on the preset position, thereof can furnish either one of said tone color signals, or a mixture of said two signals at a predetermined ratio, to said variable means, whereby the tone color signal obtained at the output terminals may be changed over from one to the other or to a mixture of the two signals at a predetermined or a variable ratio.

The nature, principle, and utility of the invention will be more readily apparent from the following detailed description with respect to preferred embodiments of the invention when read in conjunction with the accompanying drawings, in which like parts are designated by like reference numerals.

BRIEFDESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a functional block diagram of a principal part of an electronic musical instrument in which the tone color changing device according to the present invention is utilized;

FIG. 2 is a circuit diagram of a tone color changing device which constitutes an embodiment of g the present invention; and

FIGS. 3 and 4 are circuit diagrams of the same device which constitute further embodiments of the present invention.

DETAILED DESCRIPTION Referring first to FIG. I, there is illustrated a principal part of an electronic musical instrument comprising a tonegenerating device or sound source 1, switching circuits 2, a keyboard 3, filters 4, 6, tone levers 5, 7, and a tone color changing device 8 according to the present invention. The tone color changing device 8 is indicated as having two input terminals A and B receiving two tone color signals, and an output terminal 0, and when the device operates, either one of the tone color signals introduced into the terminal A and B through the filters 4 and tone levers 5 or the filters 6 and tone levers 7, or a mixture of these two signals at a predetermined ratio, or a variable ratio can be obtained at the output terminal FIG. 2 illustrates an example of the tone color changing device of the simplest construction and constituting an embodiment of the present invention. In this example, the input terminals A and B are connected through the respective mixing resistors 11 and 12 a selector switch 13. The selector switch 13 is further connected with proportion-selecting means comprising a switch 14 as is apparent in FIG. 2, and the switch 14 is operated, for instance, by a knee lever (or any other means which is operable without requiring hand manipulation). when the selector switch 13 and the switch 14 are in the illustrated positions, the tone color signals applied at the input terminals A and B are mixed together at an equal mixing rate, and the mixed signal thus obtained is sent out from the output terminal 0. Furthermore, at the illustrated positions of these switches, no signal passes through the switch 14, and the operation of the switch 14 by the use of the knee lever does not cause any change in the output signal obtained from the terminal 0. However, if the selector switch 13 is placed in position a, merely the tone color signal passed through the input terminal A will appear at the output terminal 0 when the switch 14 is placed at the indicated position (hereinafter called position b), and when the switch 14 is abruptly transferred to the opposite position (hereinafter called position a"), the tone color signal applied at the input terminal B will appear at the output terminal 0. This means that the tone color of any one tone in the musical scale can be changed over from that introduced through the terminal A (hereinafter called tone colorA to that introduced through the terminal B (hereinafter called tone color B geover of the tone color, for instance, from the tone color A to the tone color 8" or vice versa can be accomplished by a unidirectional shifting of the knee lever. More specifically, since the selector switch 13 in this device consists of a two-circuit three-position switch and the proportion-selecting means comprising switch 14 linked with the knee lever consists of the same type changeover switch as indicated in FIG. 2, if the selector switch 13 is set at position c and the switch I4 is set at position a," as illustrated in FIG. 3, the tone color A will appear at the output terminal 0. However, when the switch 14 is shifted to position b," the tone color obtained at the output terminal 0 will be changed to the tone color B."

On the contrary, if the setting of the selector switch 13 is changed from the position c to position "a," the above described sequence of appearance of the tone color at the output terminal 0 will be reversed, i.e., the tone color 8" will appear when the switch 14 is placed at position a," and when the switch 14 is shifted to position b, the tone color A" will be obtained at the output terminal 0. From this result, it is apparent that, by shifting the switch 14 in the same direction under the action of the knee lever, the tone color imparted to tones o f the musical scale can be changed from the tone color A" to the tone color 8" or vice versa. Thus, positions a" and "c of switch 13', together with switch 14, serve as reversing switch means.

In the case where the selector switch 13 is set at the position b, a signal obtained by mixing equal proportions of the signals corresponding to tone colors A" and B will appear at the output terminal irrespective of operation of the knee lever, because the two tone color signals are not passed through the switch 14. It is possible to change the tone color from the tone color A to the tone color 8" or vice versa by previously setting the position of the switch 14 at the position b" and changing suddenly the switch 14 from said set position b to the position a."

In the above-described two embodiments, the tone color is changed from A" to B or "B" to "A" or to a mixture of the two tone colors at an equal rate. However, in the third embodiment, as illustrated -in FIG. 4, the device is so designed that the mixing ratio of the two tone color signals may be varied at will. More specifically, in this embodiment the proportion-selecting means comprises a pair of variable resistors 14a and 14b respectively are connected between the output terminal 0 and the position a of the selector switch 13 and between the same terminal 0 and the position 0" of the switch 13' respectively. These variable resistors are interlinked with the knee lever in such a manner that the resistance variations in the two of the resistors are always in opposite directions, and thus serve jointly as a signal-balancing means. For instance, when the variable resistor 14a is at high resistance and the variable resistor 14b is at low resistance value, and the knee lever is operated, the resistance value of the resistor 14a is decreased and that of the resistor 14b will be increased.

The selector switch 13 of FIG. 4 is a two-circuit three-position switch similar to that indicated in FIG. 3, and is connected in the circuit in a manner such that the variation of the tone color caused through the operation of the knee lever is merely reversed by placing the selector switch 13 in position a" or position 0 and also that the tone color is not influenced by the operation of the knee lever when the selector switch 13' is placed in the position b." With this connection, when the selector switch 13' is placed in position a or position c," the tone color of the output can be varied smoothly from the tone color B to the tone color A or from the tone color A to the tone color B. When the selector switch 13 is placed in position b," the tone color of the output obtained from the output terminal 0 will be mixture of both the tone color A" and tone color B. From these considerations, it will be apparent that the described of this example is also capable of operating in the same manner as the other embodiments of the invention described above.

Since the construction of the tone color changing device according to the present invention is such that the tone color can be changed promptly through the manipulation of the knee lever even in the course of the music performance, a novel feature of performance which was hitherto impossible is now made practicable.

Although the invention has been described in respect of its preferred embodiments, it will be apparent to those skilled in the art that various modifications and alterations may be made therein without departing from the true spirit of the invention.

lclaim:

1. In an electronic musical instrument including a signal source and means for producing two tone color signals from said signal. source, a tone color changing device comprising a pair of inputs respectively receiving the two tone color signals, selector switch means connected to said inputs and having a first position in which the signals are mixed in equal amplitude proportions, and a second position permitting selective variation of relative proportions of the amplitudes of the signals, proportion-selecting means connected to said second position of said selector switch and adapted to mix the signals in a predetermined proportion of their amplitudes, and output means connected to said first position of said selector switch means and to said proportion-selecting means.

2. A tone color changing device as defined in claim 1,

wherein said proportion-selecting means comprises a twoposition selecting switch, wherein In each of the two positions thereof one of the signals will be fed to said output means to the exclusion of the other signal.

3. A tone color changing device as defined in claim 2, wherein said selector switch means includes a third position connected with said proportion selecting switch in opposite manner to said second position, whereby said second and third positions together with said two-position selecting switch comprising reversing switch means.

4. A tone color changing device as defined in claim 3, wherein said selector switch means comprises a two-conductor three-position switch, and said proportion-selecting means comprises a two-conductor two-position switch.

5. A tone color changing device as defined in claim 1, wherein said proportion-selecting means comprises variable resistor means, whereby the mixed proportion of the amplitudes of the two signals may be adjusted over a continuous range from full strength of one signal to full strength of the other signal.

6. A tone color changing device as defined in claim 5, wherein said selector switch means includes a third position connected with said variable resistor means in opposite manner to said second position, whereby the relative proportions of the signals selected by said variable resistor means may be reversed by switching between said second and third positions.

7. A tone color changing device as defined in claim 6, wherein said selector switch means comprises a two-conductor three-position switch, and said variable resistor means comprises a pair of variable resistors ganged in reverse manner to form signal-balancing means. 

1. In an electronic musical instrument including a signal source and means for producing two tone color signals from said signal source, a tone color changing device comprising a pair of inputs respectively receiving the two tone color signals, selector switch means connected to said inputs and having a first position in which the signals are mixed in equal amplitude proportions, and a second position permitting selective variation of relative proportions of the amplitudes of the signals, proportionselecting means connected to said second position of said selector switch and adapted to mix the signals in a predetermined proportion of their amplitudes, and output means connected to said first position of said selector switch means and to said proportion-selecting means.
 2. A tone color changing device as defined in claim 1, wherein said proportion-selecting means comprises a two-position selecting switch, wherein in each of the two positions thereof one of the signals will be fed to said output means to the exclusion of the other signal.
 3. A tone color changing device as defined in claim 2, wherein said selector switch means includes a third position connected with said proportion selecting switch in opposite manner to said second position, whereby said second and third positions together with said two-position selecting switch comprising reversing switch means.
 4. A tone color changing device as defined in claim 3, wherein said selector switch means comprises a two-conductor three-position switch, and said proportion-selecting means comprises a two-conductor two-position switch.
 5. A tone color changing device as defined in claim 1, wherein said proportion-selecting means comprises variable resistor means, whereby the mixed proportion of the amplitudes of the two signals may be adjusted over a continuous range from full strength of one signal to full strength of the other signal.
 6. A tone color changing device as defined in claim 5, wherein said selector switch means includes a third position connected with said variable resistor means in opposite manner to said second position, whereby the relative proportions of the signals selected by said variable resistor means may be reversed by switching between said second and third positions.
 7. A tone color changing device as defined in claim 6, wherein said selector switch means comprises a two-conductor three-position switch, and said variable resistor means comprises a pair of variable resistors ganged in reverse manner to form signal-balancing means. 